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Space Science

Analysis of Galaxy Spin Reveals Universe Might Be Left-Handed 171

Posted by Unknown Lamer from the turns-out-we're-in-the-evil-one dept.
Taco Cowboy writes "Someone from US is claiming that the universe was born spinning and continues to do so around a preferred axis." The full paper has more details. The researchers measured the spin of a number of galaxies in the northern hemisphere; the data indicated a distinct bias toward left-handed spins. "Longo says that the chance that it could be a cosmic accident is something like one in a million. 'If galaxies tend to spin in a certain direction, it means that the overall universe should have a rather large net angular momentum. Since angular momentum is conserved, it seems it [the universe] must have been "born" spinning.'" Naturally, there is some skepticism: "Neta Bahcall, an astrophysicist at Princeton University in the US, feels that there is no solid evidence for a rotating universe. 'The directional spin of spiral galaxies may be impacted by other local gravitational effects,' she said. She believes that this could result in small correlations in spin rotation over distances less than about 200 Mpc – whereas the observable universe is about 14 Gpc in size."
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Analysis of Galaxy Spin Reveals Universe Might Be Left-Handed More

Analysis of Galaxy Spin Reveals Universe Might Be Left-Handed

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  • North of the equator? (Score:3, Funny)

    by Bardwick ( 696376 ) on Tuesday October 18, 2011 @01:40PM (#37752922)
    That would explain it.

  • If the universe spins... (Score:3)

    by Oswald McWeany ( 2428506 ) on Tuesday October 18, 2011 @01:41PM (#37752936)

    If the universe spins... what is it spinning in? "Space"?

    Does space therefore exist outside the universe (other than in some theoretical brane)?

    • Re: (Score:1)

      by Sprogga ( 893092 )
      I was going to ask that too. As of now, my head is spinning trying to understand how you could be spinning in nothing.

      • Re:If the universe spins... (Score:5, Informative)

        by osu-neko ( 2604 ) on Tuesday October 18, 2011 @02:17PM (#37753424)

        I was going to ask that too. As of now, my head is spinning trying to understand how you could be spinning in nothing.

        That's easy to wrap your head around, given that spin is relative to your center, not to any outside object. Even if you were the only object in the universe, and thus could not see things spinning around you, you could easily feel the pull of your limbs away from your center if you're spinning, or the complete lack of such if you weren't. If there were two disks in the universe, me on one and you on another, and you looked at mine and I looked at yours and each seemed to be spinning relative to the other, you might be confused as to which of us was actually spinning, and which isn't (assuming one isn't), but if we both step away from the center of our disks, one of us will feel pulled towards the edge and one won't, and this won't be relative. We won't each see the other being flung off their disks while we remain unaffected, which would be absurd, rather, we'll both observe one of us fine and the other flung into space. Or possibly we both will be, if both are disks are rotating. In any case, the rate and which we are or aren't flung off will depend entirely on the actual spin of our disks, which are relative to their own centers, and be entirely unrelated to their relative spin to each other. Trying to look at spin from an outside frame of reference will just confuse you, as spin is not, ultimately, a relative measurement, unlike linear motion which is.

        • Re: (Score:1)

          by osu-neko ( 2604 )
          tl;dr version: You don't spin "in" anything, you spin around your own axis.
        • Some people say it would be impossible for something to spin in an otherwise empty space. Even centrifugal forces would somehow depend on the other matter in the universe, and would disappear if the universe were empty. It's called Mach's principle [wikipedia.org]. I personally don't buy that theory, but quite a few well known physicists do.

        • There is a similar effect regarding translation in the Cosmic Microwave Background [wikipedia.org].

          You can detect movement with relation to an absolute reference frame, indicated by the cosmic background. The observer who's moving will observe a blue-shifted cosmic radiation towards one side and red-shifted to the opposite side.

          Linear motion isn't relative either.

    • Have we found a "center" of the universe?

    • Re: (Score:1)

      by osu-neko ( 2604 )
      No. Spinning is not linear motion, and thus, is not relative. Someone on/in a spinning object and measure the amount of spin absolutely and without reference to any outside objects.

      • Re: (Score:1)

        by osu-neko ( 2604 )
        *can* measure, that should read...

      • Re:If the universe spins... (Score:4, Informative)

        by Baloroth ( 2370816 ) on Tuesday October 18, 2011 @02:16PM (#37753412)

        Actually, it is still relative, but only using general relativity, which universalizes relativity to include accelerations such as that from either gravitational fields or rotational motion. So, the universes spinning can be generalized as a gravitational field with centrifugal force. No, I don't really understand it myself, but Einstein specifically mentions the spinning disc case in explaining general relativity, so my guess is it would apply here too.

        So we still can't say objectively that the universe is spinning. Although, this outwards acceleration could possibly explain the expansion of the universe (instead of "dark energy"). But now I'm completely guessing.

        • I'm guessing too, but wouldn't acceleration due to centrifugal force decrease as the universe expands over time? Similar to an ice skater that holds out her arms to slow a spin. My understanding is that the expansion of the universe is accelerating over time.

          Also, if the universe is spinning, wouldn't it collapse into a disk?

        • Re: (Score:2)

          by ceoyoyo ( 59147 )

          The accelerating expansion of the universe doesn't show a strong preference for any particular direction. If your conjecture were true, expansion would be accelerating along the equator of the universe and decelerating towards the poles.

        • Re: (Score:1)

          by osu-neko ( 2604 )

          Ah, yes, true. I was hoping to avoid dragging general relativity into it. My understanding, though, is that there is still a difference -- gravity and uniform acceleration are not distinguishable without outside reference -- but rotational acceleration is different as it's not uniform (your head and feet experience different acceleration, unlike the situation were you standing on the floor in a uniformly accelerating rocket, or the same rocket stationary but sitting on the surface of a planet with gravity

          • Yes, good point. Interestingly, there are various ways our universe "prefers" certain directions to others. TFA points out that amino acids tend to form left-handed. AFAIK no one really knows why. And of course there is the whole matter-antimatter thing (there should, by symmetry, be equal amounts of both. There isn't, as far was we can tell.)

            As far as saying whether the universe is objectively spinning, I think you still can under relativity (we can, for instance, say without doubt that the Earth is spinn

            • I hate to nitpick, but I had to clarify this: amino acids tend to form in roughly equal quantities of left- and right-handed isomers when synthesized by non-biological processes, but life forms use and manufacture left-handed amino acids almost exclusively.

    • Re: (Score:3, Informative)

      by BradleyUffner ( 103496 )

      If the universe spins... what is it spinning in? "Space"?

      Does space therefore exist outside the universe (other than in some theoretical brane)?

      Angular momentum can be measured relative to it's self. Objects closer to the center revolve around the axis faster than those at the outside, the different can be measures, and a direction and speed determined.

    • Re: (Score:2)

      by ceoyoyo ( 59147 )

      It wouldn't be "spinning" per se, it would have angular momentum. Like an electron has spin, i.e. angular momentum, but is not spinning in a classical sense.

    • Re:If the universe spins... (Score:4, Insightful)

      by mikael ( 484 ) on Tuesday October 18, 2011 @03:00PM (#37753962)

      BBC had a really cool animation of all the galaxies orbiting each other in the known universe. Each spiral arm galaxy has the stars orbiting the central black hole. In turn all the centre of every galaxies are trying to move in straight lines, but end up colliding, merging as well as being deflected.

      The research here measures the spin axis of each galaxy through doppler shift measurements. The side spinning towards the observer will have an opposite red-shift to the side-spinning away from the observer. From the shape of the galaxy on the camera plane, they can determine the tilt and rotation towards the camera.

      What I don't understand is how they define the top and the bottom of the galaxy (or positive axis/negative axis), in order to determine clockwise/anti-clockwise rotation. Otherwise everything is going to be spinning in one direction or the other.

      • What I don't understand is how they define the top and the bottom of the galaxy (or positive axis/negative axis), in order to determine clockwise/anti-clockwise rotation. Otherwise everything is going to be spinning in one direction or the other.

        Does that matter? If you define the axis one way you get a positive angular momentum, define it the other way you get a negative angular momentum.

        I thought the implication of this study was that if you summed all the angular momentum vectors for the galaxies in question you ended up getting a vector with significant magnitude, i.e. the angular momentums of all the galaxies don't cancel out, they aren't essentially random as one would expect if there was no net angular momentum in the universe, and there is

    • That's not even the worst of the problems. What is it spinning around? An axis? Which axis? The axis through the middle?

      What middle?

      Oooo, head hurts...

    • If the universe spins... what is it spinning in? "Space"?

      Does space therefore exist outside the universe (other than in some theoretical brane)?

      http://physicsforums.com/showthread.php?t=506988 [physicsforums.com]

  • So if I have a spinning top sitting on my desk that is not currently spinning, its angular momentum is determined by the spin of its electrons? I guess this is bad astronomy week on slashdot huh.
    • Wow - that is remarkably...I don't know what!

    • Re: (Score:3, Informative)

      by osu-neko ( 2604 )

      So if I have a spinning top sitting on my desk that is not currently spinning, its angular momentum is determined by the spin of its electrons? I guess this is bad astronomy week on slashdot huh.

      Yes, and you can tell its color by summing up the colors of its quarks, too. /sarcasm

    • Yes. The angular momentum of a top is the sum of the angular momentum of all of the atoms that make it up. That's their motion around an axis, plus the orbital momentum of the electrons, plus the spins of the electrons and quarks. Since (as far as I know) you can't transform subatomic spin into motion through space, it's usually completely ignored. But, spin and angular momentum are nevertheless considered to be the same thing still. They should average out to zero in any object of interest, so it does

      • Re: (Score:2)

        by Dunbal ( 464142 ) *

        Since (as far as I know) you can't transform subatomic spin into motion through space

        You mean, like you just did?

    • Consider.

      You push an oar through water. On each side of the oar there are 2 eddy currents, one clockwise, the other anti-clockwise. Now remove the oar and just look at the currents. You can determine that the force that created them was moving linearly, as the sum of the momentums of each eddy current = 0.

      If you were to see a pattern where the sum of eddy currents was uneven, with a bias to the left or right, then you can determine that the action that created them was itself spinning in that direction at t

  • Okay, so what is the reference frame for the universe, in which you can measure angular momentum, spin, or even velocity (or even origin)? We measure the sphere of "the observable universe" as the sphere where light could have reached us since the universe began, but we can't assume that we're the center of the WHOLE universe. Presumably since the Big Bang, all stars have been moving outward from one point, but from our vantage point (or any vantage point), all other stars are generally moving away from

    • Re: (Score:1)

      by osu-neko ( 2604 )
      Rotational motion is not linear motion. It can be measured absolutely, or if you prefer, relative to itself. There is no need to reference an outside object to determine spin, it can be measured without.

    • Pick any point in space you want. The universe has a certain angular momentum around that point, which is conserved. It is unnecessary to find, or define, the "center" of the thing to measure its angular momentum -- just pick a point. The particular value you get depends on what point you choose, but it is always conserved.

      Furthermore, rotation is not a linear motion, therefore can always be detected in an inertial frame. The only way you could fail to notice the rotation of an object is if you were also ro

  • Compare the Galaxy Zoo paper from '08 (Score:5, Informative)

    by matthiasr ( 1719724 ) on Tuesday October 18, 2011 @01:47PM (#37753020) Homepage
    http://adsabs.harvard.edu/abs/2008MNRAS.388.1686L [harvard.edu] They measured the spin of a few 100000 galaxies in both hemispheres. At first they found the _same_ preferred spin in any direction, then they started mirroring half of the galaxies before showing them to people and the effect vanished. They found no dipole.
    • Sorry, should have re-read first. It was only ~37000 galaxies.

    • Re: (Score:1)

      by KrizDog ( 95871 )
      From their paper: "In addition, half the galaxies were randomly mirrored during scanning with no visual cues as to the mirroring, and precautions against left-right bias were taken in the web interface used by the scanners. "
  • ...what does that say about all us right-handed people?

    • Re: (Score:2)

      by prefec2 ( 875483 )

      They are all wrong. I knew it. I knew it. The universe is like me. It is left handed and it has not much substance ...

  • Godel Universe [wikipedia.org], and that closed timelike loops are possible?

  • Universal North (Score:4, Funny)

    by RichMan ( 8097 ) on Tuesday October 18, 2011 @01:55PM (#37753138)

    SciFi ...
    So does this explain why, when two spaceships meet in deep space they always seem to share the same vertical orientation ?
    No matter what species and innate architetural design sense.

    • No, but it does explain why the best captains are left-handed.

    • On the one hand, this is mostly done for television/movies where it would be confusing to the viewer to have some aliens upside down. On the other hand, it would be nice if they tried to be realistic. But on the gripping hand [wikipedia.org], the Moties [wikipedia.org] didn't start doing this until they realized that humans were confused and intentionally aligned themselves to our axis even though it was not in their nature to do so...
    • Funny story:

      Do you remember the USS Reliant from Star Trek 2? It was unusual for it's time because the engines were on the bottom. They weren't supposed to be. The original design had everything the other way around, but when the model makers got the sketches "up" was mis-labled. They built the ship upside-down and the director decided to just go with it.

    • Re: (Score:2)

      by rossdee ( 243626 )

      What I don't understand is why when there is a group of ships (of the same species) moving in formation are all at the same orientation. You would think that they would be better tactically aligned in different ways so that all directions are covered by their weapons.

      • Re: (Score:2)

        by prefec2 ( 875483 )

        As you can see in DS9, big armadas form a ribbon like structure which is aligned with the opposing armada. And the ribbon cannot be evaded by flying over it or below it, you have to go left or right or through it.

    • I like how Star Trek II specifically broke the mold: "His pattern indicates two-dimensional thinking."

  • Chances of "One in a Million" :

    "According to the best estimates of astronomers there are at least one hundred billion galaxies in the observable universe." (http://www.physics.org/facts/sand-galaxies.asp)

    "This study uses 15158 spiral galaxies with redshifts 0.085 from the Sloan Digital Sky Survey." (http://arxiv.org/abs/1104.2815)

    • Re: (Score:2)

      by osu-neko ( 2604 )
      Apparently you've never taken a statistics course. As such, it's not easy to explain to you why, but as a matter of fact, the chances of some conclusion being right or wrong based on a random sampling depends only on the size of the random sample, not on the size of the population the sample was taken from. The same odds apply regardless of whether it's 15158 out of a million, a hundred billion, or a trillion trillion. This, however, does assume it is a truly random sample. The criticism of this result

      • I was just quoting. (But about your comment, if there were only 15,160 galaxies altogether, or two more than in the sample, surely the chance of error would be smaller)

    • Re: (Score:2)

      by ceoyoyo ( 59147 )

      That's one in a million universes, not one in a million galaxies.

  • If this is true, and the Universe is spinning, wouldn't galaxies in a direction diverge from us faster?

  • Ned Flanders will be thrilled.

  • It probably spins the other way south of the galactic equator.

  • Maybe we've just been looking at it upside-down?

  • Observation error? (Score:3)

    by StripedCow ( 776465 ) on Tuesday October 18, 2011 @02:10PM (#37753340)

    IANAP, but I guess a single proton spinning with an enormous speed in the opposite direction may null the angular momentum.

    Perhaps he just missed that one proton.

    • Also, not a physicist, but since things with mass still have a maximum speed I don't think this is a problem.

  • There is a growing school of thought that suggests the Big Bang was the "Whitehole" side of a Blackhole forming in our parent universe. If our universe has angular momentum that would correlate to the angular momentum of the collapsing star when it reached singularity. This would be indicative of at least a precipitating event that lead to the Big Bang precipitating our universe.

    Unfortunately, there are so many things that determine chirality (handedness) including the angular momentum of super-massive hot

    • Re: (Score:2)

      by mikael ( 484 )

      And if every universe has black holes, each black hole becomes a connection to a white-hole/smaller universe. So we end up with a fractal multiverse.

    • Re: (Score:2)

      by oreaq ( 817314 )

      If our universe has angular momentum that would correlate to the angular momentum of the collapsing star when it reached singularity

      White holes are not formed by gravitational collapse but are "only" the "other side" of eternal black holes. At least in theory ...

  • Wait (Score:4, Insightful)

    by Arancaytar ( 966377 ) <arancaytar.ilyaran@gmail.com> on Tuesday October 18, 2011 @02:17PM (#37753422) Homepage

    What does "left-handed spin" even mean when there is no "up"?

    If we see a galaxy spinning clockwise, then someone looking at it from the other side (facing us) will see it rotating the other way. If they're all spinning the same way when viewed from our perspective, does that also mean we are at the center of the universe?

    • ^^ This

      There is no "top" or "bottom" of a galaxy - such directions (or positions?) are subjective when you're looking from the outside of a galaxy.

    • There is an up. There is what we call the north pole of the Milky Way galaxy. Basically, what they are asking is if other galaxies are generally spinning in the same direction as the MWG. They look up (toward where the galactic "north pole" is pointing) and see which ones are spinning the same way and then look down toward where the south galactic pole is pointing for the same. What they found is that in general, the ones above us tend to rotate counterclockwise and the ones below us tend to rotate clockwis

    • Probably the same way we determined the North Pole as being the top of our planet. All the important people were in the Northern Hemisphere, and we really like being on top.

  • How do you know what side you are looking at (top or bottom) to determine correctly in which direction it is spinning? IS there a top or bottom? I highly doubt it...
  • The universe only seems left handed. If it ever gets into a sword fight with another universe, it will wait for a dramatically opportune time and then announce, "I am not left handed!" (You'll know this has happened when suddenly you are inside-out.)

    • The universe only seems left handed. If it ever gets into a sword fight with another universe, it will wait for a dramatically opportune time and then announce, "I am not left handed!" (You'll know this has happened when suddenly you are inside-out.)

      How do we know it hasn't happened already?!

  • I read the pdf [arxiv.org] linked from the /. link. Despite the fact that the paper is full of technical jargon, I tried to sift through and glean some sense out of it, but I just can't figure out how they can reason that a galaxy has a "left" or "right" spin when such a determination is dependent on the observer's position relative to the galaxy.

    • Re: (Score:2)

      by danlip ( 737336 )

      I think left and right are arbitrary (as is positive and negative for charge and north and south for magnetism). But if the universe has no net spin you would expect a 1:1 distribution, and they are saying there is a bias.

  • Fine (Score:1)

    by eyenot ( 102141 )

    More evidence that our observable, perceivable universe even to its furthest reaches is not "all there is". You cannot find context for sidedness within a unary axiom.

  • The Universe Might Be Left-Handed?
    I think it's just using it's left hand for a different sensation...
    cumming soon, new galaxies spurting into existance!

  • Now won't that negate a bit of gravity and be the source of the cosmological constant?

  • "Longo says that the chance that it could be a cosmic accident is something like one in a million.

    So, it IS an accident?

  • I'm no scientist, but electrons spin around neutrons, moons spin around planets, planets spin around stars, stars spin around black holes, why is it outrageous to thing the galaxies are spinning around something?.. there is stuff out there that humans can't comprehend. If there were more universes revolving around something even larger, we would NEVER know!

  • Does anyone know whether this is likely to have an effect on scales other than the galactic?

    For instance, on small chaotic systems.

  • I have often wondered if the Universe might be the single particle at the center of a black hole, which are always created with a high spin. I understand that this particle takes the shape of a disk due to its rotation, rather than collapsing to a single point. It would explain why galaxies are spreading apart rather than joining together - somehow the stretching of the black hole translates into a 3D effect on the 'inside'. If the black hole were not spinning, I would expect matter in the universe to conde

    • Unfortunately, I can't think of any way to test this hypothesis

      To test the nature of an entire universe from a frame of reference outside of that universe? No, I should think not.

      I was under the impression that not all black holes rotated, at least at speeds great enough to flatten a singularity into a disk. Are you sure you are not thinking of a wormhole?

      As for the rest of your speculation. I admit that the idea of the entire universe being one supermassive black whole is tantalizing in a way. After all, we believe that every galaxy has a massive black whole at its ce

  • They're always trying to put their spin on everything. Well, they succeeded.

  • there was an excess of left... rotating spiral galaxies in the part of the sky toward the north pole of the Milky Way

    I wonder what the Tea Party will make of this. Oh sorry I forgot, they don't even like reading newspapers. Science won't even make their radar.

  • Big whorls have little whorls
          That feed on their velocity,
      And little whorls have lesser whorls
          And so on to viscosity.

    So now we know how big a big whorl is.

  • The radius of the observable universe is about 14Gly, not 14Gpc; only off by a factor of Pi (not exact, but a handy mnemonic), but still, like the old saying goes "Off by a factor of Pi is still wrong."

    --MarkusQ

  • The actual paper is here: http://arxiv.org/abs/1104.2815 [arxiv.org]

    Here is a FAQ entry about rotation of the universe and how general relativity would describe it: http://www.physicsforums.com/showthread.php?t=506988 [physicsforums.com]

    There's nothing intrinsically wrong with the idea. It's perfectly consistent with all the known laws of physics. There is in fact no well-established physical principle that should make non-rotation any more likely than rotation. There are other techniques for detecting rotation of the universe (see t

  • Why else would he have said to a room of politicians including then-president Bush "Reality clearly has a liberal bias."? Yup, the universe spins left. He called it.

  • Hmm (Score:1)

    by Anonymous Coward

    There's something sinister about these findings.

  • YOU spin around universe!

  • What is this "hand" of which you speak? The vast majority of the inhabitants of the universe have tentacles!

  • I always knew that the Universe was a sinister [etymonline.com] place.

  • Did anyone else click on the link thinking this was regarding a new Samsung phone?

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